Abstract
Eye colour is a highly transmissible and discernible trait in humans. A genome-wide association scan for variants associated to eye pigmentation was carried out on a large group of individuals coming from the Silk Road. Significant associations were detected not only with HERC2 (P-value=4.99 × 10−37) and OCA2 (P-value=4.51 × 10−9) genes but also with CTNNA2 gene (P-value=4.06 × 10−8). Moreover, the multifactor dimensionality reduction analysis clearly showed the effect of HERC2 haplotype over OCA2 mostly associated with SNP, thus enabling a highly accurate eye-colour prediction. Finally, the regression tree analysis showed that individuals carrying a given combination of haplotypes have a significant probability to show a blue or green/grey iris colour as compared with brown, with a gradient from west to east.
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Acknowledgements
We thank Laura Esposito, Angela D’Eustacchio, Federico Fornasier, and Emmanouil Athanasakis for their technical support. We also thank Terra Madre organization and the Terra Madre communities who participated in the project. This work is part of the scientific activities carried out within the expedition Marcopolo2010–2012 and it has largely been benefited from funds coming from the sponsors of the scientific expedition.
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Ulivi, S., Mezzavilla, M. & Gasparini, P. Genetics of eye colours in different rural populations on the Silk Road. Eur J Hum Genet 21, 1320–1323 (2013). https://doi.org/10.1038/ejhg.2013.41
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DOI: https://doi.org/10.1038/ejhg.2013.41
